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1.
The geographic distribution of the populations of a species are influenced by the spatial structure of the ecosystems, the environmental factors and the presence of geographic barriers. The Neotropical otter, Lontra longicaudis, is widely distributed throughout the Americas, where a wide range of environmental conditions and geographical features could promote genetic and morphological variation on the three currently recognized subspecies. In this study, we combined phylogeographic, morphometric and environmental niche modelling analyses to examine whether: (1) genetic variation is associated with the presence of barriers to gene flow and/or hydrography; (2) genetic and morphologic variation are associated with environmental variation; and (3) the observed variation in L. longicaudis populations corresponds to the previously defined subspecies. We found strong phylogeographic structure between the northern (L. l. annectens) and the two-southern subspecies (L. l. longicaudis and L. l. enudris), and although shallower, we also detected genetic differentiation between the two South American subspecies. Such genetic differentiation corresponds to the hydrography and to the geographical barriers characteristic of the distributional area of the species. We found a correlation between the shape of the skull and mandible with the environmental variation through the distribution of the species, and we rejected the hypothesis of niche equivalency and similarity between the three identified genetic lineages, suggesting adaptations to different environmental conditions. Our results support that the variation in environmental conditions, in concert with geographical barriers to gene flow and hydrography, have led to population divergence of L. longicaudis along the Neotropics. These results have important taxonomic implications for the species and its conservation.  相似文献   

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A synopsis of all Neotropical species of Cyathea with bipinnate fronds is presented. This artificial group includes 27 species with entire or very shallowly lobed pinnules. The provided key includes together, for the first time, species that had been previously treated in three different genera: Sphaeropteris, Trichipteris, and Cyathea. Full synonymy and geographic distribution is provided for each species. A second-step lectotype is designated for Cyathea marginalis.  相似文献   

5.
Identifying patterns and causes of species displacement is important from the viewpoints of ecology and evolutionary biology as this phenomenon affects community structure. Here I review the species displacement between Liriomyza trifolii (Burgess) and Liriomyza sativae Blanchard (Diptera: Agromyzidae) in Japan. These two species and Liriomyza huidobrensis (Blanchard) originated from the New World and are considered to have invaded Japan from around 1990 to the early 2000s. During this period, L. trifolii was apparently displaced by L. sativae, but the direction of displacement in Japan has been contrary to that observed between the same two species in the USA and China. While the displacement of L. sativae by L. trifolii in these two countries can be attributed to the lower insecticide susceptibility of L. trifolii there, species displacement in the opposite direction in Japan is probably due to the relatively high fecundity of L. sativae and differential effects of the introduced parasitoid Dacnusa sibirica Telenga (Hymenoptera: Braconidae) on both Liriomyza species, except in the south of the country.  相似文献   

6.
The phylogenetic relationships and phylogeography of two relatively rare Macaronesian Lactuca species, Lactuca watsoniana (Azores) and L. palmensis (Canary Islands), were, until this date, unclear. Karyological information of the Azorean species was also unknown. For this study, a chromosome count was performed and L. watsoniana showed 2n = 34. A phylogenetic approach was used to clarify the relationships of the Azorean endemic L. watsoniana and the La Palma endemic L. palmensis within the subtribe Lactucinae. Maximum parsimony, Maximum likelihood and Bayesian analysis of a combined molecular dataset (ITS and four chloroplast DNA regions) and molecular clock analyses were performed with the Macaronesian Lactuca species, as well as a TCS haplotype network. The analyses revealed that L. watsoniana and L. palmensis belong to different subclades of the Lactuca clade. Lactuca watsoniana showed a strongly supported phylogenetic relationship with North American species, while L. palmensis was closely related to L. tenerrima and L. inermis, from Europe and Africa. Lactuca watsoniana showed four single-island haplotypes. A divergence time estimation of the Macaronesian lineages was used to examine island colonization pathways. Results obtained with BEAST suggest a divergence of L. palmensis and L. watsoniana clades c. 11 million years ago, L. watsoniana diverged from its North American sister species c. 3.8 million years ago and L. palmensis diverged from its sister L. tenerrima, c. 1.3 million years ago, probably originating from an African ancestral lineage which colonized the Canary Islands. Divergence analyses with *BEAST indicate a more recent divergence of the L. watsoniana crown, c. 0.9 million years ago. In the Azores colonization, in a stepping stone, east-to-west dispersal pattern, associated with geological events might explain the current distribution range of L. watsoniana.  相似文献   

7.
Rinorea, the second most species-rich genus in the Violaceae, has been shown to be polyphyletic with four separate clades recovered in phylogenetic studies. Among these clades is the Rinorea crenata group, which is composed of three Neotropical species. This group has been shown in family- and genus-level molecular phylogenies to be resolved outside of a large clade representing Rinorea s.str. Based on phylogenetic, morphological, and anatomical evidence, Bribria, a new genus, is segregated from Rinorea s.str. and described, with new combinations made for its three species: Bribria apiculata, Bribria crenata, and Bribria oraria. In addition, two new sections in Rinorea s.str. are described to accommodate the remaining Neotropical species: Rinorea sect. Rinorea and Rinorea sect. Pubiflora, which correspond to Group IIa Rinorea and Group IIc Pubiflora, respectively, in W. H. A. Hekking’s monograph of Neotropical Rinorea.  相似文献   

8.
Acrocomia is one of the most complex genera to understand in the Neotropical Arecaceae, and there is no consensus on the number of species in the genus. A comparative study of leaf anatomy was conducted on seven species of Acrocomia: one with a wide distribution in the Americas (A. aculeata), five endemic to different regions of Brazil, Bolivia and Paraguay (A. emensis, A. glaucescens, A. hassleri, A. intumescens and A. totai) and one endemic to Cuba (A. crispa). Characters that unify the species of Acrocomia include the following: epidermis covered with cuticle, hypodermis on both sides of the leaflets, non-vascular fiber bundles, and primary and secondary vascular bundles. The shape of the leaflet margin, the distribution of the primary vascular bundles and fiber bundles, the number of idioblasts with raphides and the size of the vascular bundles, along with other characteristics, were used to distinguish these species in Acrocomia.  相似文献   

9.
The bush-cricket genus Lluciapomaresius Barat, 2012 is endemic to the Iberian Peninsula. It includes at least seven species, most of which are narrow endemics restricted to single or few mountain ranges across the Peninsula. All of them are currently included under different categories in the IUCN red list. One of the species listed as data deficient is Pantel’s Saddle Bush-cricket L. panteli (Navàs 1899), an iconic species of the Montsant Natural Park. Up to now, it was thought to be restricted to few square kilometres in the Montsant range, in southern Catalonia (north-east Iberian Peninsula). The species was at some point suspected extinct, but it was rediscovered in 2000. More recently, a new species, L. nisae Olmo-Vidal 2017, was described based on specimens found in neighbouring Llaberia range, about 20 km south from Montsant. In this study, we present new data based on a systematic sampling of Lluciapomaresius across known and nearby locations in Montsant, Llaberia and surrounding ranges. The records and collected specimens allow us to provide a better delimitation of the actual distribution range and to conduct a detailed morphological study to shed light on the degree of differentiation of populations in different parts of the range, further supported by DNA sequence data of mitochondrial and nuclear genes. Our results show that L. nisae is a synonym of L. panteli as judged by the small genetic and morphological variability, better interpreted as the result of local differentiation of populations following post-glacial isolation. We further confirm the extremely small ranges and isolation of the Lluciapomaresius populations and propose to move the species towards the EN (endangered) category in the IUCN Red List. Additional research on the still unknown aspects of its biology and ecology is needed to implement reasoned and effective conservation measures that ensure its survival.  相似文献   

10.
There are four new species of the Neotropical Anacharitinae genus Acanthaegilips Ashmead, 1897: A. boyacensis sp. n., A. curvis sp. n., A. timidus sp. n., and A. truncatus sp. n. The diagnostic characters of this new species and data about their morphological variability and similarities with other Acantahegilips species are discussed. An updated key of genus Acanthaegilips is included.  相似文献   

11.
The subgenus Pocusogetus Rtt. of the genus Otiorhynchus Germ. is revised. The subgenus includes O. rosti Strl., O. shapovalovi Davidian et Yunakov, O. obsulcatus Strl., O. fischtensis Rtt., and O. gusakovi sp. n. closely related to O. fischtensis (both from Mt. Fisht, the Western Caucasus). O. fischtensis is transferred from the subgenus Vicoranius Rtt., its lectotype is designated. A key to species of Pocusogetus is given. The systematic position of the subgenera Pocusogetus and Vicoranius in the genus Otiorhynchus is discussed. New data on the geographical distribution and ecology of the little-known species of the subgenera Obvoderus Rtt., Pseudoprovadilus Magnano, and Clypeorhynchus Yunakov et Arzanov are given. Some features of ecological differentiation between Otiorhynchus species in the alpine and subalpine zones of the Caucasus are discussed.  相似文献   

12.
Invasive species are one of the greatest threats to biodiversity, due to competition, predation, pathogen spread, and hybridization. The latter may remain undetected and impair the survival of species, due to genetic admixture and hybrid swarming (i.e., interbreeding between hybrid individuals and backcrossing with parental species). The impact of invasive species remains poorly studied in the Neotropical ichthyofauna, particularly when considering the potential for hybridization between native and introduced species. Due to fisheries importance and its commercial value, species of the Prochilodus genus have been introduced to other catchments in Brazil. Here, we evaluate the introduction of non-native Prochilodus species and the potential effect of hybridization with the native migratory fish P. hartii. To evaluate possible introgression of Prochilodus spp. to P. hartii in the Jequitinhonha river basin (JRB), we employed a morphogenetic approach, analysing 219 specimens sampled from a broad extent of the river basin. Morphological analyses using meristic characters were incongruent with molecular identification by DNA barcoding (COI) in 22.83% of the analysed specimens. Haplotypes from three non-native species (P. argenteus, P. costatus, and P. lineatus) were recovered from specimens morphologically identified as P. hartii. Hybridization between P. hartii and introduced species was confirmed using co-dominant nuclear microsatellite markers. We observed a pronounced introgression pattern in this Neotropical basin, and paradoxically, despite being one of the most abundant migratory species native to the JRB, due to ongoing levels of introgression, P. hartii’s genetic integrity and conservation might be affected.  相似文献   

13.
Individual generalist predators often have more specialized diets than their populations do. Individual specialization (IS) is influenced by ecological opportunity, intraspecific competition, and interspecific competition, although the effects of these parameters are inconsistent across studies. We investigated IS in five species of frogs and toads, Anaxyrus americanus, A. fowleri, Lithobates catesbeianus, L. clamitans, and L. sphenocephalus. We used the natural history and ecology of each species to predict which parameters would influence IS. Our predictions were supported for some species but not others. We predicted IS would be positively influenced by resource diversity in all species, but this prediction held for only three species, with the relationship significant in A. fowleri and L. catesbeianus and marginally significant in A. americanus. We also predicted that interspecific competition would have a negative relationship with IS in L. clamitans because L. catesbeianus is competitively superior to L. clamitans and likely to suppress its foraging options. This prediction was upheld. Finally, we predicted that IS in A. americanus, A. fowleri, and L. clamitans would be influenced by intraspecific competition. However, IS was not influenced by intraspecific competition in any species, a surprising result given that intraspecific competition has traditionally been assumed to be the ecological parameter with the strongest effects on IS. Many previous studies did not simultaneously consider all three ecological parameters, which may have increased the apparent importance of intraspecific competition for IS. Our results revealed that the ecological parameters affected IS differently even across closely related and ecologically similar species, and demonstrated that these differences are sometimes predictable based on natural history. This study also suggests that sympatric ecological speciation based on IS may be rare because the ecological parameters driving IS are inconsistent across species, and the strength of their effects on intraspecific diet variation varies in space.  相似文献   

14.
Synanthedon vespiformis L. (Lepidoptera: Sesiidae) is considered a rare insect in Sweden, discovered in 1860, with only a few observations recorded until a sex pheromone attractant became available recently. This study details a national survey conducted using pheromones as a sampling method for this species. Through pheromone trapping we captured 439 specimens in Southern Sweden at 77 sites, almost tripling the number of previously reported records for this species. The results suggest that S. vespiformis is truly a rare species with a genuinely scattered distribution, but can be locally abundant. Habitat analyses were conducted in order to test the relationship between habitat quality and the number of individuals caught. In Sweden, S. vespiformis is thought to be associated with oak hosts, but our attempts to predict its occurrence by the abundance of oaks yielded no significant relationships. We therefore suggest that sampling bias and limited knowledge on distribution may have led to the assumption that this species is primarily reliant on oaks in the northern part of its range, whereas it may in fact be polyphagous, similar to S. vespiformis found as an agricultural pest in Central and Southern Europe. We conclude that pheromones can massively enhance sampling potential for this and other rare lepidopteran species. Large-scale pheromone-based surveys provide a snapshot of true presences and absences across a considerable part of a species national distribution range, and thus for the first time provide a viable means of systematically assessing changes in distribution over time with high spatiotemporal resolution.  相似文献   

15.
The northern Neotropical region is characterized by a heterogeneous geological and climatic history. Recent studies have shown contrasting patterns regarding the role of geographic elements as barriers that could have determined phylogeographic structure in various species. Recently, the phylogeography and biogeography of Quercus species have been studied intensively, and the patterns observed so far suggest contrasting evolutionary histories for Neotropical species in comparison with their Holarctic relatives. The goal of this study was to describe the phylogeographic structure of two Neotropical oak species (Quercus insignis and Quercus sapotifolia) in the context of the geological and palaeoclimatic history of the northern Neotropics. Populations through the distribution range of both species were collected and characterized using nine chloroplast DNA microsatellite loci. Both oak species showed high levels of genetic diversity and strong phylogeographic structure. The distribution of genetic variation in Q. insignis suggested an influence of two major barriers, the Isthmus of Tehuantepec and the Nicaraguan Depression, while Q. sapotifolia exhibited a genetic structure defined by the heterogeneity of the Chortis highlands. The haplotype networks of both species indicated complex histories, suggesting that colonization from the Sierra Madre de Chiapas to central Mexico and from the north of the Nicaraguan Depression to the Costa Rican mountains may have occurred during different stages, and apparently more than one time. In conclusion, the phylogeographic structure of Neotropical oak species seems to be defined by a combination of geological and climatic events.  相似文献   

16.
Non-native insect pests are often responsible for important damage to native and agricultural plant hosts. Since Drosophila suzukii Matsumura (Diptera: Drosophilidae) has become an important pest in North America and Europe (i.e., in 2008), the global production of soft thin-skinned fruits has faced severe production losses. In the southern Neotropical region, however, the first record of D. suzukii occurred in 2013 in the south of Brazil. It has also been recorded in Uruguay, Argentina, and Chile. Despite its recent occurrence in the southern Neotropical region, the fast dispersion of D. suzukii has inspired local research efforts in an attempt to mitigate the consequences of this insect pest invasion. In this forum, we explore the current status of D. suzukii in southern Neotropical regions, discussing its future perspectives. Additionally, we attempt to draft activities and a research agenda that may help to mitigate the losses caused by D. suzukii in native and commercial soft-skinned fruits produced in this region. Currently, D. suzukii appears to be well established in the south of Brazil, but considering the entire southern Neotropical region, the invasion panorama is still underinvestigated. The lack of studies and regulatory actions against D. suzukii has contributed to the invasion success of this species in this region. Considering several peculiarities of both the pest biology and the environmental of this region, the authors advocate for the need of intensive and integrative studies toward the development and implementation of area-wide integrated pest management programs against D. suzukii in the southern Neotropical region.  相似文献   

17.
Data on habitats, food plants of larvae and adults, feeding, mating, oviposition, larval and pupal development, natural enemies, and distribution of seven weevil species (Lixus canescens F.-W., L. iridis Ol., L. myagri Ol., L. punctirostris Boh., L. subtilis Boh., L. incanescens Boh., and L. brevipes Bris.) are given. New host plants of L. canescens and L. iridis are revealed. Gall induction by L. brevipes is reported for the first time. Distribution of all the species in Ukraine and Russia (the latter based on the literature) are given in more detail. Information on the known and potential economic importance of every species is provided.  相似文献   

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The cryptic wood white Leptidea juvernica is one of a newly-discovered species complex comprising three morphologically similar species in Europe. In the British Isles, L. juvernica is absent from Great Britain, but is widespread in Ireland, where it has experienced recent declines; it is classed as a priority species in Northern Ireland. Using a mark–recapture approach, this study aims to elucidate the population and spatial ecology of L. juvernica based on a population resident on a small, suburban site and to propose conservation measures. The results demonstrated that populations of L. juvernica, even on small sites, can reach high numbers during the peak flight season. Unusually for European Pieridae, there was only weak evidence of protandry in this population, possibly reflecting weather conditions prior to the flight season. The spatial distribution and abundance of L. juvernica was associated with the distribution of its larval host-plants, as well as maintaining close proximity to south-facing habitat edges for shelter. Males had a closer association to sheltered habitat edges, whilst females were found more commonly on open ground with a shorter sward which was the preferred egg-laying habitat. Long vegetation in sheltered areas was important for roosting during periods of non-activity. These results inform conservation measures which will benefit L. juvernica; appropriate measures focus on habitat management providing a mosaic of open, semi-natural grassland interspersed with tall vegetation, scrub, and trees.  相似文献   

20.

Background

Liriodendron is a genus of Magnoliaceae, which consists of two relict species, Liriodendron chinense and L. tulipifera. Although the morphologies are highly similar, the two species exhibit different adaptive capacity. Dehydrins (DHNs) are abiotic stresses resistant proteins in planta, which are associated with adaptive evolution. To better understand the evolution divergence between L. chinense and L. tulipifera and how DHN genes are associated with adaptation evolution, we firstly investigated the DNA polymorphisms of the LcDHN-like gene in 21?L. chinense and 6?L. tulipifera populations.

Results

A 707?bp LcDHN-like gene was cloned, which included a 477?bp open reading frame (ORF) and coding 158 amino acids. 311 LcDHN-like gDNA sequences were obtained from 70?L. chinense and 35?L. tulipifera individuals. The AMOVA and phylogenetic relationship analysis showed significant differences between the two species. A higher genetic diversity was observed in L. tulipifera compared to L. chinense, in consistent with the higher adaptive capacity of L. tulipifera. Our data also suggested that the LcDHN-like genes’ polymorphisms were under neutral mutation and purifying selection model in the L. chinense and L. tulipifera populations, respectively. The distinct expanding range and rate between the two species, haplotypes shared only in L.chinense’s nearby populations, and wide dispersals in L. tulipifera could contribute to the obscure east-west separation in L. chinense and entirely unordered phylogeny in L. tulipifera. The completely separated nonsynonymous substitution at position 875 and the higher range scope of aliphatic index in L. tulipifera populations may be related with its higher adaptive capacity. Taken together, our study suggests LcDHN-like gene is a potential mark gene responsible for adaptive evolution divergence in Liriodendron.

Conclusions

Significant differences and completely distinct haplogroups between L. chinense and L. tulipifera showed that the two species have evolved into different directions. The more widely distribution, earlier haplogroups divergence events, and richer SNPs variations in L. tulipifera could imply its stronger adaptation in this species. And potential effect of the allelic variations in LcDHN-like gene may reflect the difference of water stress and chill tolerance between L. chinense and L. tulipifera, which could provide some information for further adaption evolution studies of Liriodendron.
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